Present day microelectronic circuits usually operate at moderate power levels and can be adequately cooled by natural or forced convection of air. Cooling can be enhanced by attaching heat-generating devices to thermally conductive heat sinks which spread the heat over a large surface area for contact with the circulating air. Circulation of cooled water through heat sinks and other heat exchangers have also been utilized for cooling microelectronic circuitry.
In some cases, large amounts of heat are generated and the conventional cooling techniques described above are inadequate. For example, high speed switching circuitry, such as is used in computers and telecommunication switching circuits, generate large amounts of heat. Also, power supply circuits frequently have devices with high power dissipation. Cryogenic cooling systems, wherein the electronic devices are immersed in a cooling liquid such as liquid nitrogen have been utilized to meet high capacity cooling requirements. While these systems are effective in providing high capacity cooling, they are complex and expensive. Therefore, cryogenic cooling systems are not cost-effective for relatively small systems having only a few very hot components.
It is an object of the present invention to provide improved apparatus for cooling electrical circuit components.
It is another object of the present invention to provide circuit component cooling apparatus having high cooling capacity.
It is yet another object of the present invention to provide circuit component cooling apparatus which is effective for use with one or a few heat-generating components.
It is still another object of the present invention to provide circuit component cooling apparatus which does not use a toxic heat transfer medium.
It is a further object of the present invention to provide circuit component cooling apparatus with an open loop heat transfer system wherein a cooling gas is released into the atmosphere after use.
It is a further object of the present invention to provide circuit component cooling apparatus which is relatively simple and low in cost.